                        Astronomy Picture of the Day

    Discover the cosmos! Each day a different image or photograph of our
      fascinating universe is featured, along with a brief explanation
                    written by a professional astronomer.

                              2025 September 18

                           Comet C/2025 R2 (SWAN)
                 Image Credit & Copyright: Team Ciel Austral

   Explanation: A new visitor from the outer Solar System, comet C/2025 R2
   (SWAN) also known as SWAN25B was only discovered late last week, on
   September 11. That's just day before the comet reached perihelion, its
   closest approach to the Sun. First spotted by Vladimir Bezugly in
   images from the SWAN instrument on the sun-staring SOHO spacecraft, the
   comet was surprisingly bright but understandably difficult to see
   against the Sun's glare. Still close to the Sun on the sky, the
   greenish coma and tail of C/2025 R2 (SWAN) are captured in this
   telescopic snapshot from September 17. Spica, alpha star of the
   constellation Virgo, shines just beyond the upper left edge of the
   frame while the comet is about 6.5 light-minutes from planet Earth.
   Near the western horizon after sunset and slightly easier to see in
   binoculars from the southern hemisphere, this comet SWAN will pass near
   Zubenelgenubi, alpha star of Libra, on October 2. C/2025 R2 (SWAN) is
   scheduled to make its closest approach to our fair planet around
   October 20.

                    Tomorrow's picture: it's complicated
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       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Amber Straughn Specific rights apply.
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